东营凹陷基底断裂走滑活动对油气成藏的影响  

Effect of Strike-Slip Activity of Basement Faults on Hydrocarbon Accumulation in Dongying Sag

作　　者：周维维 董有浦 肖安成[2] 吴磊[2] 毛黎光 李洪革 Zhou Weiwei;Dong Youpu;Xiao Ancheng;Wu Lei;Mao Liguang;Li Hongge(Kunming University of Science and Technology,Kunming 650093,China;College of Earth Sciences,Zhejiang University,Hangzhou 310058,China;School of Geosciences and Surveying Engineering,China University of Mining and Technology,Beijing 100083,China;BGP Inc.,China National Petroleum Corporation,Baoding 071000,China)

机构地区：[1]昆明理工大学国土资源工程学院,云南昆明650093 [2]浙江大学地球科学学院,浙江杭州310058 [3]中国矿业大学地球科学与测绘工程学院,北京100083 [4]东方地球物理公司,河北保定071000

出　　处：《地球科学》2023年第7期2718-2732,共15页Earth Science

基　　金：国家自然科学基金项目(Nos.41802215,41762017,41672206);中国石油天然气股份有限公司科学研究与技术开发项目.

摘　　要：弱变形构造带是沉积盆地盖层中客观存在的构造现象,并且与油气聚集关系密切,一般可以通过不同地质单元(次级断层、油藏、圈闭、相带、凹陷、岩体、潜山等)的有规律排列等现象进行识别.为了初步揭示盖层变形带变形强度与油气聚集规模这一问题,首先在渤海湾盆地初步识别出40条盖层变形带,然后应用变盖层厚度和变剪切强度的构造物理模拟实验方法研究基底断裂走滑活动对盆地沉积盖层产生断层的过程.应用SPSS软件,对基底走向滑动量、横向滑动量、实验盖层厚度、雁列缝长度等参数进行了多元二次函数拟合.根据东营凹陷八面河、王家岗地区古近系各时期地层厚度、构造图R剪切长度、实验估算的张扭角度,计算出了各个时期的基底断裂走滑量;在模拟实验各阶段充注染色石油,结合凹陷实例建立了基底断裂走滑早期R剪切单一通道运移‒孤立聚集、早中期R剪切主通道运移‒雁列串珠状聚集(王家岗)、P剪切主通道运移‒断续带状聚集、全通道运移‒连续带状聚等成藏模式(八面河);最后指出盖层变形带上的R剪切增压变形段,R、P剪切交汇段是油气勘探有利目标区.The development stage of the fault deformation zone refers to the weak deformation(strong concealment)zone developed in the sedimentary cover of the basin,which is the product of the early and middle stages of the formation and evolution of the fault zone.It is difficult to identify because of the lack of obvious fracture surface(zone)and significant displacement.It has been found that the weakly deformed tectonic belt is an objective tectonic phenomenon in the sedimentary basin cover,and is closely related to oil and gas accumulation.It can be recognized by regular arrangement of different geological units(secondary faults,oil reservoirs,traps,facies belts,depressions,rock masses,buried hills,etc.).In order to reveal the deformation intensity and hydrocarbon accumulation scale of cap cover deformation zone,the key issue of oil and gas geology,this paper takes the Dongying Sag as the research object and applies variable caprock thickness and the structural physical simulation experiment method in which variable shear strength is used to study the process of basement fault strike-slip activity on the formation of faults in the sedimentary caprock of the basin.Using SPSS software,taking the sliding amount of the basement/the thickness of the experimental cover layer(D_(NBD))as the independent variable x1,the amount of lateral sliding/the thickness of the experimental cover layer as the independent variable x_(2)(x_(2)=x_(1)×tanα)and the length of the echelon seam/the thickness of the experimental cover as the dependent variable y,multivariate quadratic function fitting was performed.According to the strata thickness,shear length of structural map R and experimentally estimated tensional and torsion angles by experiment in different periods of Paleogene in Bamianhe(strong strike slip)and Wangjiagang(weak strike slip)areas of Dongying Sag,the strike-slip amounts of the basement faults of Bamianhe and Wangjiagang fault zones in each period were calculated.At each stage of the simulation experiment,dyed oil was charg

关 键 词：渤海湾盆地 断裂活动性 盖层变形带 弱走滑断裂 基底断裂 成藏模式 石油地质学. 

分 类 号：P618.13[天文地球—矿床学]